Process of treating and preserving wood.



A. F. BA 'RRY DECD.

M. E. BARRY. EXECUTIHX.

PROCESS OF TREATING AND PRESERVING WOOD.

APPLICATION FILED APR. 19, I915- Patented Sept 12,1916.

2 SHEETS-SHEET I.

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WITNESSES:

burrs trams rarer-tar is mun-mm- ANGUS l BARRY, OF KANSAS CITY, MISSOURI; MARY ELLEN BARRY EXECUTRIX OF SAID ANGUS FERRY BARRY, DECEASED.

'lE'lEtOCESS F TREATING AND PRESERVING WOOD.

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citizen of the United States of America, residing at Kansas City, in the county of Jackson and State of Missouri, have invented 3 certain new and useful improvements inthe Processes of Treating and Preserving Wood, of which the following is a specification.

The invention relates particularly to the processes of wood preservation in which the sap is removed from the sap channels by a preliminary sweating process, to which the wood is subjected in a heated vacuum, prcvious to the application of the preservative,

as described in the specification forming a part of the Letters Patent of the United States granted to me under date of October 24, 1911, and numbered 1006713.

The object of the present invention is to treat various kinds of wood, which have previously resisted the penetration of the preservative, such as non-porous woods, fir being one well known species, and also for the treatment of such Wood as has been casehardened from exposure to the Weather.

The further object of the invention is to subject the wood to be treated. while ina heated vacuum to cause sweating of the wood, and without breaking the vacuum, equalize the expansion of the rings of the non-porous Wood with the other portions of the wood and also of the case-hardened portion of the Wood, so as to prevent checking or splitting of the wood, from unequal expansion, and effect a complete penetration of the preservative.

an open position, and the wood to be treated upon a car, which is mounted on the track pails within the cylinder; and Fig. 2 is a transverse, vertical, sectional view of the cylinder or retort, taken upon the line at, a", in Fig. 1', and showing one of the steamcondensing chambers in section, the door of the cylinder being closed.

7 indicates the retort, one end being closed, the other end having a dooropening 6, adapted to be hermetically closed by the door 10, which door is secured by bolts 11.

Specification of Letters Batent. Patented Sept. 1L2, 19%;

Application filed. April 19, 1,915.

Serial No. 22344:.

temperature within the retort, and 16 thepipe connecting the gage with the retort 7.

16 indicates the temperature bulb.

17 represents a gage for indicating the degree of vacuum Within the retort, and 18 the pipe connecting said gage With the retort.

18 is a valve in pipe 18.

19 represents a gage for indicating the oil pressure within the tank, and 20 the pipe leading fromthe gage to the retort or cylinder. a

20- is the valve in pipe 20.

23 is the exhaust pump for exhausting the air from the cylinder retort 7, and 22 the pipe leading from the} retort to the 21 is a valve in the' pipe 22, for opening up the retort to the action of the exhaust pump -28. l

26 is a spherical steam-condensing case having the chamber 25, and 24 is a pipe for steam leading within the receiver 26, and 27 is the cut-off valve in pipe 24.

28 is a pipe for the supply of air, leading within the receiver 26 and in av position directly opposite the discharging end of the steam pipe 242.

29 is a valve in the pipe 28.

31 is a dome within the lower section of chamber 25, of receiver 26, the dome having a deflecting convex surface 30.

32 indicates, the pipes for supplying the preserving oil or creosote to the retort, and 33 are the cut-citvalves in pipes 32.

34 indicates a-thermometer for indicating the temperature within the retort 7, around the heating coil 12 and 34* the temperature bulb.

36 represents a compressed air storage tank, and 35 a pipe connected with said tank and with the retort 7 and at the cen- 'tral point of the closed end 9 of said retort.

'- 37 represents a y of the retort or in said pipe.

under my process, such as throu through pipe 22', by

' densation being removed thereby, and re-.

35*ii1d-icates the valve for admitting the compressed air from tank '36 to the retort. gage on the tank 36, for indicating the air pressure in tank 36.

38 indicates a check valve in the pipe 35.

.40 indicates the. discharge pipe for the air in thebottom and forward end portions cylinder 7, and 39 the valve The wood which is subjected to treatment may be instanced lumber, for railroad uses, is stacked longitudinally upon the flat bottom car 5, and the car with its load is moved Within the door -'opening 16,. of theretort or cylinder 7, on

the track rails 8, which retort is adaptedto receive the lumber in large: quantities for. treatment. The hinged door 10,-of theretort, is then closd, and secured by the bolts 1l,-hermetically sealing the door opening 6.

boiling point of water in vacuum indicated by the temperature gage 15, the valves 13* and 14* are closed, and valve 21,- in pipe 22,

leading from the bottom of the retort, is

partially opened, and suction is produced upon the, heated air within the retort, graduallyforming. a vacuum 'withinsaid retort suflicient to distributethe heated air throughout the retort and downwardly heate air producing a'sweating of the wood, and rapid release of the sap from the cellular portions of the Wood, leaving. the cellular portions fully open, the sap falling to the bottomof the cylinder and being removed the suction pump' 23, the opening of the exhaust valve being 1 gradually increased during the} action of the pump, the,v accumulation of" liquids of conabsorption by the wood prevented. In this treatment the glutinous scale formed on the walls of the cellular portions dissolves and passes out in a soluble condition with the sap, through pipe 22, by the action ofthe pump 23, whlle the volume of heated air is drawn downwardly from the top of the retort by a slow and progressively increasing vacuum. The determination of. the drypp o h the wood, the action of the rarefied,

ness of the wood is indicated by the decreased amount of condensation obtained.

- The absence of moisture in the wood. be-

ingtreated being perceived in the meager discharges of the sap, the rings of the nonporous portions of the wood, and the casehardened portions of thewood are softened and made equally receptive for theoil penetration. The succeeding step-in the process is to produce in the heated, dry atmosphere withintheretort, sufficient vapor to soften the rings of the case hardened parts of the wood without breaking the vacuum within;

theretort, so essential to preserve, while the action of the vapor is taking place upon said rlngs or case-hardened parts. The temperature within the cylinder being new at the proper degree, as indicated by the tempera ture gage 15, and the vacuum by the vacuum.

gage 19, the valve 20", in the pipe 20, is opened to show the which is constantly maintained at the boilgrees of. vacuum, which 1s as follows through the steam condensing chamber 25,, in the chamber 95, upon the opening of the valve 27, and air is admitted to the chambern25 through the- 'pipe 28, upon the opening of the valve 29,

' the steam and air entering in the line of the. I

and from oppodiameter of the receiver '25 site directions, the air coming into direct contact with the steam and condensing the steam into moisture above the convex surface 30 ofthe dome 31, in the lower portion of the case 24. The moisture from condensation passes through said opening 30", in the dome '30, into the retort 7 without breaking the-vacuum in the retort, the same vacuum being produced within the case2 l, from the action of the vacuum pump 23. The temperature of the case 24 during the condensation of the steam is found to be cold. The moisture from condensation of amount of vacuum,

the steam, upon entering the retort 7 passes over the heated coil 12, within the retort,

penetrates the cellular and case-hardened portions and the rings of the non-porus Wood equally, the expansion of said parts in the heated vacuum permitting specifically the softening ofthe hardeped gum in the case-hardened portions and rings of the nonporus'wood, and a uniform penetration of the. vapor is obtained by-absorption, and

without inixury to the fiber of the wood, the degree of eat of the vapor being approximately below the boiling point of water, hencethe wood; being dry in the heated vacuum, the hardened gum yields readily to the action of the vapor. Upon exposure of the wood to the vapor, for aperiod of time, approximately thirty, or forty minutes, necessary to soften the rings of tii runmemo? po l bus wood, which is found by frequent tests, the valve 21 in the pipe 22, and the Valves 27. and 29 in the respective pipes 24 and 28, are closed. The preserving oil,su'ch as creosote, is then admitted to the retort through the pipes 32, upon opening oi? the valve 33. The temperature of the oil is from 90 to 200 Fahrenheit, and enters the retort under pressure, destroying the vacuum. The heated oil passes over the steam heated coil12, and through the wood charge, and a subsequent pressure of H0 or more pounds is applied to the oil, which is indicated by the oil pressure gage 17.

When the penetration of the wood and its rings, or the case-hardened portions is coxnp leted, the valves 33, in pipes 32, closed. Compressed air, which is cooled by expan- "sion to a temperature of to 40 Fahrenheit, is then admitted to the retort through the pipe 35, containing check valve 38, and ladlng from the compressed air storage tank 36, through said pipe, and centrally to the end plate 9, of the-eretort, at approximately 80*to 100 pounds, as indicated by the gage 37. The outlet valve in the pipe 4H) is then opened to a small extent, to reduce the pressure now on the oil to 80 or 100 pounds pressure, until theprcssure on the oil and the air obtains equal pressure, and these pressures maintained for the necessary period of oil penetration. The gradual discharge of the oil from the retort, and the action of the cold, compressed air undep expansion, forces the body of the oil througl'ij pipe 40, in a restricted quantity, while holding the air pressure as indicated by gage 37, on tank 36, at to pounds upon the hot preserving oil. Asthe volume of the preserving oil decreases, the volume of cold, compressed. air is increased, and passes through the wood charge, contracting the wood, so that the fiber structure is not injured, and the'cellular portions and the rii'igs of the non-porous wood receive equal penetration. Upon the full opening of the valve 39, in pipe 40, the excess of oil is blown out of the retort by the expanded air, the cold air drying the wood, while the wood is within the retort. The valve is then closed, the door 10 to the-retort opened, and the preserved lumber removed therefrom,

The value of the process is understood by those skilled in the art, and has been prac tically demonstrated by me, in a section. of the country in which the species of timber knownias Douglass fir is indigenous, The rings of the nonporous species of wood, which are seasoned and contain the hard ened gum, under all previously known processes split from the cellular portions, and

the only successful method has been under even the surrounding moisture from the sap,

will not aii'ectthe case-hardened part of wood, except to separate or. part from the other. In my process the expansion and contractioneof one part will not check the vase-hardened part of the wood, because no vulcanizing methods are, used, nor could be employed in a heated, dry vacuum without breaking the vacuum, and hence, I have discovered and put into successful operation the only known process for the treatment of non-porous and case-hardened Wood.

Not only fir, but hemlock has been successfully treated under my process, the re sult being proven that the tensile strength or" the wood is increased, as well as its longevity.

Having fully described my invention, what I nowclaim as new and desire to secure by Letters Patent is:

1. The herein described process of treating case-hardened and non-porous wood for the enetration of a preservative without chec ring of the Wood, which consists in subjecting the Wood to a heated vacuum and supplying a vapor below the boiling point of water for the absorption of the vapor equally by the cellular and case-hardened portions or rings of the wood without breaking the vacuum.

2. The herein described process of treatingcase-hardened and non-porous wood for the penetration of a preservative without checking of the wood, which consists in introducing within a retort Within which a heated vacuum is maintained, of a determinate amount of moisture converted by the heat within the retort into a vapor which acts upon the case-hardened ortions of the wood and without breaking tiie vacuum.

.3, The herein described process of treating non-porousand case-hardened wood for the penetration of a preservative, which consists in heating the air above the wood, being treated within a retort, applying suction to create a vacuum, and thereby drawing down the rarefied heated air through the wood charge to cause sweating oi the wood, and then drawing a determinate amount of moisture which is converted into vapor by the heat within the retort through the wood charge without breaking the vacuum.

4. The herein described process of treating non-porous and case-hardened wood for the penetration of a preservative, which consists in heating the air above the wood being treated within a retort, applying suction to create a vacuum, and thereby draw ing down the rarefied heated air through the wood charge to cause sweating of the wood, and then drawing a determinate amount oi? moisture converted into vapor by the heat within the retort throughthe wood charge without breaking the Vacuum, then subjecting the'wood to hot preserving oil, thereby destroying the vacuum.

5. The herein described process of treating and preventing checking of case-hardened and non-porous wood, consisting in heating the air above the'wood being treated in create a vacuum within the retort, condensmg steam with the aid of air to form moisture, drawing suflicient moisture convertedby the heat within the'retort into vapor a retort, and thenapplying suction to.

through the wood charge without break- I 

